fossil
Marine invertebrate fossils (Brachiopods and Gastropods)
Phylum Brachiopoda and Class Gastropoda
Hardness: 3-4 (calcite composition), Color: Light brown to grayish-tan, Luster: Dull/Earthy, Structure: Bilateral symmetry in brachiopods and spiral coiling in gastropods.
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Physical properties
Hardness: 3-4 (calcite composition), Color: Light brown to grayish-tan, Luster: Dull/Earthy, Structure: Bilateral symmetry in brachiopods and spiral coiling in gastropods.
Formation & geological history
Formed through permineralization or as internal molds (steinkerns) in sedimentary marine environments. Likely from the Paleozoic or Mesozoic era (approx. 66 to 541 million years old).
Uses & applications
Educational tools, scientific research into ancient marine paleoecology, and popular items for amateur fossil collectors.
Geological facts
Brachiopods look like clams but are biologically distinct; they possess a lophophore (feeding organ) and their shell symmetry is across the valves rather than between them.
Field identification & locations
Look for symmetrical ribbed shell impressions or spiral snail-like shapes in limestone or shale outcrops. Often found in abundance in fossiliferous limestone layers.
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